Taxonomy term

september 2017

Less-developed countries with high climate risk need better access to weather and climate data

Rising seas, more persistent droughts and more frequent severe weather events are predicted to occur in the coming decades as the planet continues warming. In a new study, researchers who analyzed spending internationally on weather and climate information services (WCIS) suggest that access to reliable WCIS is becoming more vital for communities and governments looking to assess their vulnerability and to safeguard people and property amid changing climates.

22 Sep 2017

Down to Earth With: Paleobiologist Gregory Erickson

As an undergraduate at the University of Washington, Gregory Erickson wasn’t sure what he wanted to do. He started out as an engineering major, then dabbled with getting a degree in wildlife management. In 1986, having taken numerous science courses, he happened to compare notes with his best friend, a geology major, and realized he was just a few courses shy of obtaining a geology degree himself. Eager to finish college, Erickson signed up for a class in vertebrate paleontology focusing on dinosaurs — a decision that ultimately changed his life.

22 Sep 2017

Volcanism triggered end-Triassic extinction

The end-Triassic mass extinction exterminated up to three-quarters of all species on land and in the oceans 201 million years ago. This die-off opened up ecological niches and allowed for, among other changes, dinosaurs to diversify and spread across terrestrial ecosystems during the rest of the Mesozoic. Volcanism has long been implicated in the extinction, but whether it had a major impact on the planet at the time has remained unclear. In new research, scientists observed elevated mercury concentrations in extinction-aged rocks from around the world. Because volcanism is the main nonanthropogenic source of mercury in the environment, the findings suggest that volcanic activity was likely the main extinction trigger at the end of the Triassic.

21 Sep 2017

Jerusalem tower facelift reveals it's 1,000 years younger

Jerusalem is one of the oldest cities in the world, dating back to at least 2400 B.C. Downhill from the heart of the city is Gihon Spring, a year-round natural fount that was likely the primary water source for the ancient city. Defensive fortifications built around the spring, known as the Spring Tower, were originally dated to the Middle Bronze Age, around 1700 B.C., but a new study reveals the tower could be as much as 1,000 years younger.

19 Sep 2017

Glass shards reveal a fiery history in Ethiopia

Chains of volcanoes and a lava lake pepper the landscape of the Afar Triangle in northeastern Ethiopia, where eruptions and earthquakes are byproducts of the rifting that is literally ripping Africa apart, but recent eruptions have been docile. Now, scientists studying ash deposits from the last 40,000 years are showing that dangerous, explosive eruptions present an ongoing hazard, striking the region every 1,000 years on average.

18 Sep 2017

Cassini's legacy after two decades at Saturn

Scientists on Earth have received the last submission from the Cassini spacecraft. It descended into Saturn’s atmosphere at 122,500 kilometers per hour, which caused it to melt, thereby ensuring that Saturn’s moons Titan and Enceladus would remain protected from possible contamination by any errant Earth microbes. Cassini scientists had considered other options for the spacecraft’s end, including leaving it to float endlessly in space or parking it in orbit around Saturn. But ultimately, they chose to have it descend into Saturn’s atmosphere after deciding the data that could be returned from the descent were more valuable than any further data it might obtain by remaining in space. Scientists will make discoveries from these data for decades to come.

15 Sep 2017

Mars class of 2020: A diverse group of missions takes aim at the Red Planet

As many as six missions to Mars might launch in summer 2020, representing a growing and increasingly diverse interest in interplanetary space exploration.
15 Sep 2017

A great time to land on Mars

The 2020 window represents an especially good opportunity for missions looking to reach the Martian surface because of favorable environmental conditions on the planet early in 2021 when the spacecraft will arrive. The elliptical shape of Mars’ orbit means that the planet is, at times, much closer to or farther from the sun, so the amount of sunlight hitting the planet varies dramatically through the Martian year. Meanwhile, the tilt of Mars’ axis, as on Earth, leads to a progression of seasons as the orientations of the northern and southern hemispheres with respect to the sun change regularly and oppositely. The combination of Mars’ orbit and tilt drives an annual cycle of swings in atmospheric pressure of up to about 25 percent as carbon dioxide freezes out of, or sublimes into, the atmosphere.

15 Sep 2017

Making oxygen with MOXIE

The MOXIE (Mars OXygen In-situ resource utilization Experiment) instrument on NASA’s 2020 rover is designed to demonstrate technology that can generate oxygen from carbon dioxide in the Martian atmosphere. Scaled-up versions of the technology could one day be used to produce the large amounts of fuel needed to boost rockets back off the planet’s surface, as well as to create breathing oxygen for human settlements.

15 Sep 2017